Su Qing, a modern toxicology expert, transmigrates into the body of Liu Qingyuan, the legitimate daughter of the Jing’an Prefecture. The original Liu Qingyuan was set up by her half-sister and stepmother and drowned. Within half a month, she is destined to face a deadly trap: she will be accused of having an affair and thrown into a pond to drown. Using her knowledge of toxicology and her sharp wits, she first escapes the ten-day death trap, then strikes a marriage agreement with the ailing heir, Xiao Yu. By improving rouge, she gains control of a vital economic lifeline, and through deftly navigating the rules of propriety, she brings down the Liu family’s long-standing corruption case.
Along the way, she uncovers her true identity as the orphaned daughter of the late Empress. Xiao Yu, who is actually a prince investigating the case, and she go from using each other to falling deeply in love. In the end, with wisdom and courage, she destroys the corrupt clan and wins a new life for herself, her birth mother, and the court.
